Hi Krista Sherer,
Reviewing through your description, I see where you had also submitted this as a case in your customer group. Please find a summary of the case below:
I've taken a look at your instance and it appears that these two streams have Notify Users set to "Off" on their settings, which is why the options to enable emails and adjust the activity drop down are greyed out. These streams are set up at a system level for All Registered Users, so changes to how these notifications are set up would need to be done by an Admin if you wish to have email notifications sent for these streams to all of your registered users.
This document outlines our News feature quite extensively, I'd suggest checking out the section on Everyone News Streams which are the ones that users are not able to toggle on/off in their preferences as they are global settings: All About the News Feature